Oxidation of ammonia by iron, manganese and nickel oxides – Implications on NOx formation in chemical-looping combustion

Artikel i vetenskaplig tidskrift, 2019

We report an experimental evaluation of NH3 oxidation over three types of oxygen carrier materials under conditions relevant for chemical-looping combustion. The active metal and the oxidation state of the oxygen carrier is crucial to NO formation from NH3. Although, the carriers tested were equally efficient in terms of CO oxidation they differed from 0 to 6000 ppm of NO in the off-gas. The nickel based carrier produced the lowest amounts of NO and the manganese based the most. The sensitivity to the oxidation state also differed between the materials. The results stress that NO formation should be consider in the choice of oxygen carrier material as well as in the design of chemical looping-combustion systems.